Apparatus for grinding precious stones.



E. LOESSER.

APPARATUS FOR GRINDING PRECIOUS STONES.

I APPLlCATllON FILED JULY I3. |914.

5 sHEETsTsHEEr 1.

Patented Jan.4,1916.

E. LOESSER.

APPARATUS FOR GRINDING PREclous STONES.

AFPLICATIN 'FILED JULY 13, 1914.

Patented Jilin. 4, 1916.

5`sHEETs-SHEET l2.

vw@ nto@ E. LOVESSER. APPARATUS FOR GRINDING PRECIOUS STONES.

APPLICTION FILED JULY I3, 1914.

4Patented 'Jan'. 4, 1916.

5 SHEETS-SHEET 3.

.HHHHhh. l l I l I I IIL.

` E. LoEssEH. APPARATUS FOR GRINDNG PRECIOUS STONES.

APPLCATLON FILED JULY` I3. 1914. y I

' Patented Jan. 4, 1916.

E. LOESSER.

APPARATUS FOR GRINDING PRECIOUS STONES. APPLICATION FILED JULY 13,'1914.

17,166,843. Pate'rft'ed Jan. 4, 1916.

5 SHEETS-SHEET 5.

citizen 'of the United States,

'uNrrEn sraTEs 'rArENfr OFFICE. l

EnNEs'r LoEssER, or GLEN RIDGE, NEW JEEsEY,'AssieNon 'ro NEW Diamo-ND Por.-

ISHING TOOL COMPANY OF OF NEW YORK.

AMERICA, INC., OF NEW'. YORK, N. Y., A CORPORATION APPARATUS FOR GRINDINGPRCIOUS S'ILONTELS.v

To all whom it may concern.'

Be it known that I, ERNEST LoEssEn, a residing in Glen Ridge, county of Essex, State of New Jersey, have invented certain new and useful Improvements in Apparatus for Grinding- Precious Stones, of which the following is a Specification.

lhis invention relates to improvements'in the art of lapping precious stones, and has particular reference to a mechanism adapted to grind the facets of suchv stones.

One object of invention is to provide a mechanism Iadapted to grind the facets automatically to the exact degree required.

Another vobject is toA secure this result withoutv the use of highly skilled and eXpensive labor.

Another object is to provide .a mechanism' that will automatically and positively remove the stone from the lapping wheel at 'the instant 'the' lapping process has been -sufciently cont'nued.

Another object is to provide an electricallyl actuated ldevice to produce this result which utilizes a `quick-throw switch.

Another object is toprovide means to signal the operator whena grinding operation has been completed and the mechanism requires further manipulation; and still other objects will appear in the following description and the appended claims.

Referring to the drawings: Figure 1 isa side elevationof the machine; Fig. 2 is a tain features;

vided with the usual lap wheel 10 mounted.

plan view; Fig. 3 is a plan view with parts omitted and others broken away to show cer- Fig. 4 is a ,sectional elevation taken on the line of Fi-g. 3; Fig. 5 is a sectional velevation taken on the line 5-5 of Fig. 3; Fig. 6 is a front elevation with'parts shown'in section Fig. tion taken on the line 7-7 of As shown in Fig. 1, the machine'is proupon a vertical shaft 11 and driven by suitable means,as a pulley 12 and belt 13. l It is a dop 14 4and dop further provided with holder 15 by which theangle and number of facets to be ground'upon the stone is determined. T-lie'se parts are not *further* de- Specification of Letters Patent.l Application mea my is, i914.. serial No'. 850,655.

7 is a sectional eleva Fig. 3; Fig. 8 is a sectional plan taken on the line 8-8 of Fig.' 5; and Fig. 9 is a sectional elevation` taken onthe lline 9-9 of Fig. 5.

Patented an. 4, 1916.

,scribed as they form no 'part-of the present invention.

The dop support, as a tong 16, as shown in Figs. 1 and 2, which is equipped with adjustable feet 17, 17 at its rear end resting on the bed plate 22, while its forward end carries the dop holder 15. The tong vand dop holder are connected byy a spindle 18 attached to the dop holder and vertically slidable in the tong, to which it may be clamped in its adjusted position by the nut 19. The, weight of the tong or vsupport and the parts carried thereby rests normally upon the two feet 17, 17 and the stone carried by the dop.

In addition however, an auxiliary and temporary rest for the tong is provided by a pin 20` yertically mounted on the frame 20B and adjusted by a nut v21. This pin is setf holder is carried by a suitable to hold the tong in its substantially parallel mechanism actuated by the movement of-the tong, and a detector controlled mechanism for elevating the tong.

The detector mechanism is best shown in Figs.- 2, 3 and 5, and comprises an angle lever-having a short arm 23 and a long arm 24, each pinned to a shaft 25 journaled on pivots y26, 26, carried by the frame. The

located below and in the path of the tong, as shown.` The long arm extends to the rear of the machine and terminates in avertical extension 28 and latch lug 29. The latch lug and arm' 24 are normally supported by a drop switch, as best shown inFig. 5.

The drop switchis pivbted to a vertically movable block 30 at'the point 31 and inzontal projection 34 supportingl the latch 29, a vertical projection 35 resting Vagainst-.the end of the latch lug 29 to hold the switch open-and a contact terminal 36 fastened to and insulated 4from the block 3 0.- The block short arm is provided with an offset pin 27 cludes a. handle 32, a contact cam 33, a hori- 30 carrying the switch as shown inFigs. 5

and 8 ismounted in a vertical `guid'eway- 37 at the rearend of lframe 20 and is supported bya spring 38." A vertically disposed adjusting screw 39 at the upperpart block 30 to act in conjunction .with spring- 38 to adjust said block. To provlde against` lost motion or any laterall play-of the block 30 and at the same time preserve :its ease ofY adjustment, a lateral spring40 1s inserted` in a recessin-the'block 430, as shown 1n Fig..

8 and bears against the adjacent wall of the guide-way, giving the block a. smooth frictionalcontact with the other. guide-wall so that it is held steady at all times.

lin the` operation of the detector mechanism, the contact of the descending` support with the pin 27, as the stone is ground away, elevates the rear end 28 of the arm 24, the

- latch 29 rising above the extension 35 of the when the arm is rocked by the cam 46.

mounted as shown in Figs. 1,

switch, permitting the latter to fall"forward by gravity to the dotted line position shown in Fig. 5, in which position the switch cam 33 contacts with the terminal 36, closing a circuit which controls the tong -Velevating .mechanism This elevating mechanismis best 'shown in Figs. 3, 4, 5 and 6,and comprises a .solenoid 41 attached to the frame 20, a plunger'42 connected b a pivoted link 43 to an arm 44 pinned to s aft 45,. Upon shaft 45 is a segment 42 arranged beneath the extension of.. the plunger to which the link 43 is connected and which is adapted to su port. the weight of the plunger 42.

he energizing of the solenoid causes the arm 44 to move to the left as shown in Fig. 4, rocking the shaft 45 anti-clockwise. Upon the. shaft 45 lower arm 47 attached to a sleeve 48 carried by shaft 25 and a spring 49 surrounding, the sleeve operates tokeep the follower arm in contact with the cam.l rlhe armis further provided with a camming extension 50 which contacts'with an adjustable'plate 50 carried by the tong and, elevates the trililg e shaft'45 carries also a commutator sector 51 provided with an insulating segment 52, and which is in contact with a brush terminal 53 of the solenoid 41.

The mechanism as a whole is adjustably frame 20 bein slotted as at; 54 so that it may be held a justably to the bed by bolt, as at 55. The frame is equipped with ways 56 upon which the guide 56a for one of the tong feet is slidable, the guide bein clamped inthe desired position by plate 5 and screw 58. As shown in Figs. 1 and 2, cyllndrlcal members 58, extending upwardly from the frame 20a, prevent lateral movement of the tong durln thel lapping operation.

he electric connections are best shown in Fig. 2 in which the battery is represented at 59 and is connected to the solenoid`41 by conductors 60,61. Fromthe solenoid the circuit runs-from tenal 62 to brush 53, sector 51 to the ground. 'llhe second battery dop with the angle,

is a cam 46 coacting with a foltector in raised thenl verticallyI adjusted so thatl the top of the projection 35 'will justpass under the" end of the latch lug 29., thus providing a,

.in -Fig. 5, and

are provided to from battery meeste connection-63/divideslat switch point 64, one -l path being through the conductor 65, the

scribed, it will be seen that when-the sector 51 and the brush 53 are in electrical contact, a relatively small current Hows eontinuously through the solenoid and the lamp, as they are in single circuit, li hting the lamp but not adecting be closed and the dro switch is tripped, the cam 33 'will ground tiie terminal 36 placing the lamp and solenoid in multiple circuit, whereby th'e greater part of the current will iow from the battery directly through the solenoid andy energize the elevating mechanism; and that with the movement "of the latter mechanism, the ant-iclockwise movement of the sector 51 will bring the insulated segment 52 under the brush 53, breaking both the lamp and the solenoid circuits. a

rlhe first facet of a set or series of facets of the stone, which is suitably' -held by the dop holder fset at the requisite is ground o-r polished to the desired size with the tong 16 set in horizontal position, the tong then being supported by the feet 17 and the stop 20, adequately adjusted, with the stone in contact with the lap. The iirst facet may of course have beenotherwise previously ground, and with its dop set in the apparatus with the parts thereof adjusted as described. The

the adjustable plate of the tongAk and with the rear end of the long arm 24 of the deposition. The drop switchis knife-edge escapement for the drop switch. When the stone is set for another facet to be formed'by the lap the front end of the tong will of course be raised and be out of contactv with the pin 27; the drop switch is now inopen position, as shown by the full lines is soheldby the latch 29, rest- 34, with its end ing on the projection against the front face of the -projection 3 5.

'lhe plunger or armature 42 of the solenoid 41 is at this time 'set in outer position, as shown in Figs. 2, 4 and 5, and the current 59 flowing through the solenoid andthe lamp 66 1n single circuit insuliciently energizes the solenoid to cause it to act on its plunger but lights the lamp. N ow when the facetl is ground away to the same depth as the previously ground facet `the tong has assumed its orlginal set posithe'solenold; that'if the switch pin 27 of the short arm of the detector, or tong raising mechamsm'controller, will now be in contact with tion and the latch 29 releases' the diop switch, thus changing the circuitfto place the solenoid and lamp'in multiple, and with ,l the switch 70 closed the lamp-66 is short circuited and by its extinguishment notifies completed. Practically all .of the current -now flows through' the solenoid, which,

drawing in the. plunger 42, causes the tong to be raised through themedium' of the camming device 50, as before described, and

, so vertically lifts the stone away from the l'ap. By-the time the device '50 has moved into practicallyvertical'position under thel tong, and so holds it up, the insulating )block 52 hasmoved to the vbrush terminal i l 53, thus breaking the circuit, leaving all the by the solenoid be set before the drop switch *is raised'the switch 70 should then be open. It'is `obvious that many'changes mayl be madein the mechanism disclosed wit out departing from the spirit land scope ofthe invention, and I kdo not -limit myself to the particular mechanism disclosed, this' being but a particular embodiment of my inven- .tion and illustrative thereof. What is claimed: v

`1. A precious stone grinding and polishing machine, `comprising -a lap on which the stone bears, a bed-plate, ,a tong having one end resting on the lbed-plate and hav- 40 ing at its opposite free end a movement tol ward and fromthe lap, a stone holding device connected with the free end of the tong to move gradually therewith toward the lap as the grinding 'operation proceeds and to` move quickly with the tong away fromthe lap when the grinding operation is completed, normally inactive means for raising the free end of the tong and the stone holding device simultaneously away from lthe 5u' lap. and ldevices operating automatically on completion of a facet-forming operation to f bring said lifting means into active operat1on.

. 2. A precious stone grinding and polish- 5\5 ing machine, comprising a'lap on which the stone bears, a tong or support, one end of which has a free movement toward and from the lap,A a stone-holding device connected to move oincidentallyfwith the free end of the tong toward' and from the lap, normally inactive/means for raising the free end of the'tong and the stone-holding device avv-ay from the lap and devices operating-@automatically on the completion` of a facet-- 95 forming operation to bringsaidraising heattendant that the grinding operation isy 'completion of a lnormally inactlve electromagnetlc devices ling machine, comprising a movable support,

means into active operation to raise'the free end vof the-tong and thus `withdraw the stone from the lap. 1

3. A precious stone grinding and polishing machine, comprising a movable support, 50'

a sonel`iolding device carried by the support, a lap on which the stone bears, means for automatically raising the support to move the' stone vertically away from the lap Aupon the completion of a facet forming operation ,and a signal device operated in conjunction withl the support raising means.

`4. .A` precious stone grinding and polishing' machine, comprising a lap, a tong having avfree end adapted -to move toward and from thelap, a stone-holding device carried by the-free end of thetong .and adapted to move coincidentally therewith, a swinging arm having a part acting on the under side of the tong to raise the latter, normally 1n- 85 active means for actuating said arm to raise thetong and a tripping device engaging the tong and operating .when the latter has been depressed to a suilicient extent to bring the raising me'ans'into active operation. 90 5. `A precious stoney grinding and polishing machine, comprising ar lap on which the stone bears, a movable support mounted in the frame of the machine, a stone-holding device carried by the support, means operating to raise the support and to move the stone vertically away from the lap upon the facet-forming operation,

for operating lsaid raising means and de'- vices operated by the descent of the support to bring said electromagnetic devices into active operation when a facet is completed.

6. A precious stone grinding and polishing machine, comprising a movable support,

va stone-holding device carried by the suport, a lap on which the sto-ne bears, means or automatically raising the support to move `the stone vertically away from the lap and a ,locking device for holding `thesupport in its raised position after the completion .of each facet-forming operation. 7. A precious stonegrinding and polishing machine, comprising a movable support, a stone holding device carried by the support, fa' lap onL which the' stone bears, a swinging arm adaptedto act on the, underside of the supportI and means including an electric motor device and a switch, actuated from the support, for automatically moving the arm to raisel the support and lock it in raised position with the stone away from the lap.

8. A preciousstone grinding and polish- 125 a stone holding device carried by the support, 'a lap on which the stone bears, ya

vswinging arm adapted to act on the underside of the support` means including an electric motor device v and a switch, actuated 13 from the support, for automatically moving 'the arm to raise and hold the support with the stone away from the lap and a detector acted upon by the .support for controlling the switch.

10. A precious stone .grinding and polish? ing machine, comprising a movable support, a stone holding. device carried by the (support, a'lap on which 'the stone bears,a swinging arm adapted toact onfthe underside of the support, means including an electric motor device and i a quick acting switch for automatically moving the 'arm to raise the support .fand hold the stone away c from the lap and a detector acted upon by the support and having a knife edge connection with the switch whereby the switch is suddenly released to become closed and cause the motor to be adequately energized.

11. In a precious stone grinding and polishing machine, afstone holder, a lap, a

source of electricity, an. electric motorjde-v vice adapted to move the stone holder away from the lapand` means for causing the electricmotor to become active when a facet of the stone has been duly ground or polished.

y12. 1n a precious stone grinding and polishing machine, a stone holder, a lap, a source of electricity, an electric -motor device adapted to move the stone holder awayfrom the lap, a signal lamp in circuitwith the electric motor and means for causing the electric motor to become active when a facet of the stone has been duly ground or polished.

13.,1n a precious stone grinding and polishing machine, a stone holder, a lap, a source of electricity, an electric motor device adapted to move and hold the stone' holder away from the lap, means for causing the electric motor to become active when a facet of the stone has been duly ground or polished and means controlled by the electric motor fory opening the motor circuit after the stone holder is raised.

14. In a precious stone grinding and polishing machine, a stone holder, a lap, a source of electricity, an electric motor -device adapted to move the stone holder away lfrom the lap, a signal lamp .in circuit with the electric motor during thegrinding oper- -ation and means for setting the motor and lamp in multiple circuit, whereby the motor 'modena is' adequately energizedlto raise ythe stone v holder .and the lamp current reduced to -inefhciency.

15. AIn apreciousistone grinding and polishing machine, ,a-stone holder, a lap, a

source of electricity, an electric motor device adapted to move the stone holder away from the lap, a signal lamp in circuit with the electric motorduring the grinding operation, means for setting the motor and lamp A" eiiiciency and means'controlled bythe motor i to 'open the circuit after the stone holder is raised.

16. A precious stone grinding and'polishholding device carried by the tong, a lap on whichl the stone bears, a swinging arm ing machine, comprising a tong, a stone y adapted to act on the underside of the tong, Y

means including an electric lmotor device and a switch, actuated from the tong, forV automatically moving the armv to raise the tong and hold the stone away from the lap and 'a signal lamp in circuit with the elec-v tric motor during^`-the grinding operation and placed in multiple with the motor when the switch is closed, whereby the motor becomes adequately energized to raise the tong and the lamp current reduced to inefliciency.

17. A precious stone grinding and polishing machine, comprising a tong, a stone holding device carried by the on which the stone bears, a swinging arm adapted to act on the underside of the tong, means including an electric motor device and a switch, actuated from the tong,` for automatically moving the arm to raise the tong and hold fthe stone awayfrom the la, a signal lamp in circuit with the electric motor during the grinding operation and placed in multiple with the-motor when the switch is closed, whereby the motor becomes adequately energized to raisethe tong and tong, a lap ing means, a swlnging switch inthe electric circuit and a detectordevice adapted to hold the switch open and to be acted upon by the supporting means when said means has moved a predetermined distance, to release the switch to close the circuit.

19. lncombination' with a movable supporting means or tong, an electrically actuated means adapted to raise said supporting means, a swinging self-closing switch in the lelectric circuit and a detector device adapted to hold the switch open, to beheld in operative position by the switch and to be acted upon bythe supportingm ans when said means has moved a predetermined distance,

'to release the switch to c lose the circuit.

20.1In'combination' with a movable sup.-

porting means or tong, an electrically actuated means adapted to raise said supporting '1neans, a drop switch in the electric circuit and having a vertical and a lateraljextension, a lever having one of its ends resting on the lateral eXtenslon and bearing against the vertical extenslon ofthe switch and having its other end in the path of the movable means, means for adjusting thenswitch relasupporting means,

moved a predetermined distance and the drop switch is freed to close the circuit.

21. In combination with a movable supporting means or tong, an electrically actuated means adapted to raise said supporting means, a swingmg switch in the electric circuit, means for adjusting the supporting tively to the supporting means and a zdetector device adapted to hold the switch open ,and to be acted upon "by the supportlng means when said means has moved a predewhereby said lever 1s actuated when the supporting means has termined distance,l to release the switch to tor device and a quick .acting drop switchV for automatically moving the arm to raise the support and hold the stone away from the lap, .a lever held in normal operative position by the switch and., holding the switch in open positionfand also adapted to be Amoved by the support, when said support has moved a predetermined distance, to release the switch to close the electro-motor circuit.

In testimony whereof, I have hereunto subscribed my4 name.

n vERNEST LQESSER. Witnesses :1 i I JOHN A. PERCIVA'J, L. F. BROWNING. 

